In telling the story of a true-life unsung hero a filmmaker faces many pitfalls. How often have we seen well-intentioned movies become sanctimonious and lose their dramatic edge? No such accusations can be leveled at Jim Loach’s Oranges and Sunshine, an impressive film that documents an astonishing but little-known story.

The wonderful Emily Watson plays Margaret Humphreys, whose book Empty Cradles documents her efforts, from 1986 onward, to trace the facts behind a mass deportation of “unwanted” children from England to—

Australia beginning in the 1950s. This governmental program was kept under wraps for decades, and roundly denied when Humphreys began her investigation. Most parents lost track of their children while the kids, as young as three years old, never knew what hit them. Adding salt to the wound, many of these unfortunate children suffered terribly once they arrived in Australia, turned into slaves doing forced labor.

There are many ways one could approach this shocking story. Fortunately, director Loach and screenwriter Rona Munro avoid big, emotional moments, and don’t paint Watson’s character as a saint. In fact, the conflict she faces as she becomes involved in the lives of the now-grown children who want to reconnect with their parents, and the time she spends away from her own family in Nottingham, forms a crucial part of the story.

Watson’s empathetic performance is matched by her costars, especially David Wenham as a bluff Aussie whose off-putting personality obscures the deep wounds of his childhood, and Hugo Weaving as his polar opposite, a fragile shell of a man who has never recovered from the ordeal, especially the absence of a mother in his life.

Oranges and Sunshine never plays like a “message movie.” It has a vital story to tell and does so with taste and restraint. By keeping the characters’ emotions in check, the film allows us to respond to every turn in the story, and each new revelation, in our own way. The cumulative impact is devastating. I can’t say enough about this exceptional film.